Has anyone in the NAM community custom installed an aftermarket performance muffler (i.e. Magnaflow) on a Cooper ?

Since the typical stnls. steel cat back systems don't give a "plain" Cooper much extra perfromance for the price (over $400 for maybe 2-3 more HP), I'm looking at just installing a different muffler and get rid of that monstrosity that BMW calls a muffler ...

Thanks in advance !!!!

 

Before you go hacking off that stock muffler you might want to check out the replacement cost if you need to buy a new one. Personally I do not know what they cost but i can assure you the stock muffler is a very well designed one piece unit that would be expensive to replace.

I only mention this because I have had my stock muffler off and on several times in place of my aftermarket system. It's amazing how quiet the stock muffler is after living with an aftermarket unit and although it's a little heavy it still flows quite nice for a stock engine with stock cams.

Anyway, something to think about.....I've been contemplating putting a supertrapp on my aftermarket exhaust just for kicks.....I have not seen many "Cooper" users with them installed and that's probably because it's a very contraversial muffler design on a modern engine. Anyway, I'll post pictures if I do. Best of luck.

Stuart

 

I politely disagree...have seen photos on this site (or Mini2??) where a MC owner cut open the stock muffler after he swapped it for an aftermarket.....the pipe makes a very acute angle bend within the muffler housing....most of the muffler seems to be sound deadening matl.....

I've put Magnaflows on previous cars and they show definite HP / TQ improvement....you can roll a golf ball thru that thing !!! Plus the sound tends to not be so loud compared to others.....

Maybe I should refine my question.....given the tight quarters under the MC where the muffler is sited, what Magnaflow model have other NAM members fitted up under there ???

Thanks

 

I don't think it would be hard to find a muffler to fit in place of the stock unit....Basically just look for a relatively shallow muffler with the outlet on the opposite side of the inlet. There about a 6-8" difference from side to side but any good muffler shop should be able to tack one in....Best of luck.


Stuart

 

I INSTALLED AN "OBX' complete stainless system on my car and it sounded great BUT I COULDN'T TELL MUCH DIFFERENT IN PERFORMANCE.

THE SYSTEM CONNECTED ALL THE WAY TO THE HEADER SO YOU DIDN'T HURT ANYTHING IN THE REMOVAL PROCESS. KEEP THR OLD SYSTEM.

WIFE SAID "GET THAT DXXX NISE MAKER OFF THE CAR OR I DON'T RIDE IN IT." SO I DID. I'VE BEEN MARRIED 49 YRS. AND I ATLEAST WANT TO MAKE 50.

CHECH OUT OBX WEBB SITE. THERE BASED IN CALIF.

 

There is all kinds of room under there! I just got done installing a Rouge cat back on my son's car, took all of 35 minutes start to finish. Hardest part was getting the car off the floor. Can't tell you about performance changes, as he took off for the weekend and might be back sometime Monday

Only thing I don't like about the system is the mid section clamp. It's the beefy thing in the middle. The bolt/nut portion is too large to rotate around and into the heat shield area without hitting on the shield. I'll replace it when he shows up. He just got the car on the 19th and has been driving it nonstop

 

I also have a Rogue. Take the clamp off and have it welded:smile:

 

Slangager, Smokey & Minicop;


Thanks for the replies and photos.....looks like you're right....lots of room up in there for an aftermarket muffler.....

Probably go with a 4 x 9 x 14 Magnaflow.....but first I have to get the wife out of it so I can take it to the shop....

Will post photos when completed.....cheers to NAM !!!

 

If possible you might want to rotate that clamp in any direction but straight down. That is now the lowest point under the car and the first to hit should you get low enough. We had a car come by the shop with the entire back half of the system wasted because of that.

 

Yup I agree and the plan is to either replace it or remove it completely once I get my welder fired up. And it's really not that possible, as the heat shield is rather tight right there and we could only get about 20 degrees of movement on it, any more and it hits the heat shield.